[en] Improvements in the mechanical properties of magnesia-partially-stabilized zirconia are obtained by the addition of SrO. Evidence is presented which indicates that the added SrO effectively neutralizes the detrimental effect of SiO/sub 2/ contaminant by forming a glass phase which is effected from the bulk of the ceramic during sintering. this combined effect results in the retardation of the subeutectoid decomposition reaction while minimizing retention of glass phases at the grain boundaries